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arXiv · 0707.2683

Liquid-Solid Transition and Phase Diagram of ^4He Confined in Nanoporous Glass

Keiichi Yamamoto·Yoshiyuki Shibayama·Keiya Shirahama
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Abstract

We have studied the liquid - solid (L-S) phase transition of ^4He confined in nanoporous glass, which has interconnected nanopores of 2.5 nm in diameter. The L-S boundary is determined by the measurements of pressure and thermal response during slow cooling and warming. Below 1 K, the freezing pressure is elevated to 1.2 MPa from the bulk freezing pressure, and appears to be independent of temperature. The T-independent L-S boundary implies the existence of a localized Bose-Einstein condensation state, in which long-range superfluid coherence is destroyed by narrowness of the nanopores and random potential.

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Keiichi Yamamoto, Yoshiyuki Shibayama, Keiya Shirahama. 2007-07-18. Liquid-Solid Transition and Phase Diagram of ^4He Confined in Nanoporous Glass. https://doi.org/10.1143/jpsj.77.013601

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